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Carlson KB, Dilley A, O'Grady T, Johnson JA, Lopman B, Viscidi E. A narrative review of norovirus epidemiology, biology, and challenges to vaccine development. NPJ Vaccines 2024; 9:94. [PMID: 38811605 DOI: 10.1038/s41541-024-00884-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 05/07/2024] [Indexed: 05/31/2024] Open
Abstract
Norovirus is a leading cause of acute gastroenteritis (AGE) globally. AGE resulting from norovirus causes significant morbidity and mortality in countries of all income levels, particularly among young children and older adults. Prevention of norovirus AGE represents a unique challenge as the virus is genetically diverse with multiple genogroups and genotypes cocirculating globally and causing disease in humans. Variants of the GII.4 genotype are typically the most common genotype, and other genotypes cause varying amounts of disease year-to-year, with GII.2, GII.3, and GII.6 most prevalent in recent years. Noroviruses are primarily transmitted via the fecal-oral route and only a very small number of virions are required for infection, which makes outbreaks of norovirus extremely difficult to control when they occur. Settings like long-term care facilities, daycares, and hospitals are at high risk of outbreaks and can have very high attack rates resulting in substantial costs and disease burden. Severe cases of norovirus AGE are most common in vulnerable patient populations, such as infants, the elderly, and immunocompromised individuals, with available treatments limited to rehydration therapies and supportive care. To date, there are no FDA-approved norovirus vaccines; however, several candidates are currently in development. Given the substantial human and economic burden associated with norovirus AGE, a vaccine to prevent morbidity and mortality and protect vulnerable populations could have a significant impact on global public health.
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Affiliation(s)
| | - Anne Dilley
- Epidemiologic Research & Methods, LLC, Atlanta, GA, USA
| | | | - Jordan A Johnson
- Epidemiologic Research & Methods, LLC, Atlanta, GA, USA
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Ben Lopman
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
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Callegari M, Danziger-Isakov LA, Rose A, Kaul D, Shaffer K, Chong PP, Florescu D, German K, Avery R, Nguyen MH, Wildfeuer B, Michaels MG, Green M, Guo K, Zhao L, Daud A, Ison MG. Presentation, anagement, and outcomes of norovirus in adult and pediatric solid organ and hematopoietic stem cell transplant recipients: A multicenter, retrospective study. Transpl Infect Dis 2024:e14270. [PMID: 38526183 DOI: 10.1111/tid.14270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 01/20/2024] [Accepted: 03/05/2024] [Indexed: 03/26/2024]
Abstract
BACKGROUND Norovirus (NoV) can cause chronic relapsing and remitting diarrhea in immunocompromised patients. Few multicenter studies have described the clinical course, outcomes, and complications of chronic NoV in transplant recipients. METHODS A multicenter retrospective study of adult and pediatric SOT and HSCT recipients diagnosed with NoV between November 1, 2017, and February 28, 2021. Data were obtained from electronic medical records (EMR) and entered into a central REDCap database. Descriptive statistics were calculated. RESULTS A total of 280 NoV+ patients were identified across eight sites. The majority were adults (74.1%) and SOT recipients (91.4%). Initial diagnosis of NoV occurred a median of 36 months post-Tx (IQR [15.0, 90.0]). Most NoV cases had >3 diarrheal episodes daily (66.0%), nausea and vomiting (60.1%). Duration of diarrhea varied greatly (median = 10 days, mean = 85.9 days, range (1, 2100)). 71.3% were hospitalized. Adjustment of immunosuppression, including reduction and discontinuation of mToR inhibitor, CNI, and/or MMF, was the most common management intervention for NoV. Other therapies resulted only in temporary improvement. Four patients died within 30 days and three others died by 180 days postdiagnosis. Clinically significant renal dysfunction was observed in 12.5% by 30 days and 21.4% by 180 days post-NoV diagnosis. CONCLUSION In HSCT and SOT patients, NoV frequently resulted in severe symptoms, prolonged diarrhea (30% persistent with diarrhea for >30 days), and clinically significant renal dysfunction (up to 21% of patients). Utilized therapies did not reliably result in the resolution of infection demonstrating the need for more effective treatment.
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Affiliation(s)
- Michelle Callegari
- Divisions of Organ Transplantation, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Lara A Danziger-Isakov
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
| | - Anne Rose
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
| | - Daniel Kaul
- Division of Infectious Disease, Department of Internal Medicine, Michigan Medicine, Ann Arbor, Michigan, USA
| | - Kelly Shaffer
- Division of Infectious Disease, Department of Internal Medicine, Michigan Medicine, Ann Arbor, Michigan, USA
| | - Pearlie P Chong
- Division of Infectious Diseases and Geographic Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Diana Florescu
- Infectious Diseases Division, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Kaci German
- Infectious Diseases Division, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Robin Avery
- Division of Infectious Diseases, Johns Hopkins University, Baltimore, Maryland, USA
| | - M Hong Nguyen
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Brett Wildfeuer
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Marian G Michaels
- Department of Pediatrics, University of Pittsburgh, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Michael Green
- Department of Pediatrics, University of Pittsburgh, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Kexin Guo
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Lihui Zhao
- Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Amna Daud
- Divisions of Organ Transplantation, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Michael G Ison
- Respiratory Diseases Branch, Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
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Chaimongkol N, Dábilla N, Tohma K, Matsushima Y, Yardley AB, Levenson EA, Johnson JA, Ahorrio C, Oler AJ, Kim DY, Souza M, Sosnovtsev SV, Parra GI, Green KY. Norovirus evolves as one or more distinct clonal populations in immunocompromised hosts. mBio 2023; 14:e0217723. [PMID: 37905910 PMCID: PMC10746188 DOI: 10.1128/mbio.02177-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 08/30/2023] [Indexed: 11/02/2023] Open
Abstract
Noroviruses are a major cause of acute gastroenteritis worldwide and can establish chronic infection in immunocompromised individuals. To investigate the mechanisms of norovirus evolution during chronic infection, we selected seven representative patients from a National Institutes of Health study cohort who sustained norovirus infection for periods ranging from 73 to 1,492 days. Six patients shed viruses belonging to a single genotype (GII.2[PNA], GII.4 New Orleans[P4], GII.4 Den Haag[P4], GII.3[P21], GII.6[P7], or GII.14[P7]) over the period examined, while one patient sequentially shed two genotypes (GII.6[P7] followed by GII.4 Sydney[P31]). Norovirus genomes from consecutive stool samples were sequenced at high resolution (>3,300 reads/nucleotide position) using the Illumina platform and subjected to bioinformatics analysis. Norovirus sequences could be resolved into one or more discrete clonal RNA genomes that persisted within these patients over time. Phylogenetic analyses inferred that clonal populations originated from a single founder virus and not by reinfection with community strains. Estimated evolutionary rates of clonal populations during persistent infection were similar to those of noroviruses from acute infection in the global database, suggesting that inherently higher RNA-dependent polymerase error rates were not associated with the ability to persist. The high-resolution analysis of norovirus diversity and evolution at the population level described here should allow a better understanding of adaptive mutations sustained during chronic infection. IMPORTANCE Noroviruses are an important cause of chronic diarrhea in patients with compromised immune systems. Presently, there are no effective therapies to clear the virus, which can persist for years in the intestinal tract. The goal of our study was to develop a better understanding of the norovirus strains that are associated with these long-term infections. With the remarkable diversity of norovirus strains detected in the immunocompromised patient cohort we studied, it appears that most, if not all, noroviruses circulating in nature may have the capacity to establish a chronic infection when a person is unable to mount an effective immune response. Our work is the most comprehensive genetic data set generated to date in which near full-length genomes from noroviruses associated with chronic infection were analyzed by high-resolution next-generation sequencing. Analysis of this data set led to our discovery that certain patients in our cohort were shedding noroviruses that could be subdivided into distinct haplotypes or populations of viruses that were co-evolving independently. The ability to track haplotypes of noroviruses during chronic infection will allow us to fine-tune our understanding of how the virus adapts and maintains itself in the human host, and how selective pressures such as antiviral drugs can affect these distinct populations.
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Affiliation(s)
- Natthawan Chaimongkol
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Nathânia Dábilla
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
- Laboratory of Virology and Cell Culture, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Kentaro Tohma
- Division of Viral Products, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Yuki Matsushima
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Allison Behrle Yardley
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Eric A. Levenson
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jordan A. Johnson
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Courtney Ahorrio
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Andrew J. Oler
- Bioinformatics and Computational Biosciences Branch, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Daniel Y. Kim
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Menira Souza
- Laboratory of Virology and Cell Culture, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Stanislav V. Sosnovtsev
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Gabriel I. Parra
- Division of Viral Products, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Kim Y. Green
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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Prado NDR, Brilhante-Da-Silva N, Sousa RMO, Morais MSDS, Roberto SA, Luiz MB, Assis LCD, Marinho ACM, Araujo LFLD, Pontes RDS, Stabeli RG, Fernandes CFC, Pereira SDS. Single-domain antibodies applied as antiviral immunotherapeutics. J Virol Methods 2023; 320:114787. [PMID: 37516366 DOI: 10.1016/j.jviromet.2023.114787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 07/25/2023] [Accepted: 07/26/2023] [Indexed: 07/31/2023]
Abstract
Viral infections have been the cause of high mortality rates throughout different periods in history. Over the last two decades, outbreaks caused by zoonotic diseases and transmitted by arboviruses have had a significant impact on human health. The emergence of viral infections in different parts of the world encourages the search for new inputs to fight pathologies of viral origin. Antibodies represent the predominant class of new drugs developed in recent years and approved for the treatment of various human diseases, including cancer, autoimmune and infectious diseases. A promising group of antibodies are single-domain antibodies derived from camelid heavy chain immunoglobulins, or VHHs, are biomolecules with nanometric dimensions and unique pharmaceutical and biophysical properties that can be used in the diagnosis and immunotherapy of viral infections. For viral neutralization to occur, VHHs can act in different stages of the viral cycle, including the actual inhibition of infection, to hindering viral replication or assembly. This review article addresses advances involving the use of VHHs in therapeutic propositions aimed to battle different viruses that affect human health.
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Affiliation(s)
- Nidiane Dantas Reis Prado
- Laboratório de Engenharia de Anticorpos, Fundação Oswaldo Cruz, FIOCRUZ, unidade Rondônia, Porto Velho, RO, Brazil
| | - Nairo Brilhante-Da-Silva
- Laboratório de Engenharia de Anticorpos, Fundação Oswaldo Cruz, FIOCRUZ, unidade Rondônia, Porto Velho, RO, Brazil; Programa de Pós-Graduação em Biologia Celular e Molecular, Instituto Oswaldo Cruz, IOC, Rio de Janeiro, RJ, Brazil
| | - Rosa Maria Oliveira Sousa
- Laboratório de Engenharia de Anticorpos, Fundação Oswaldo Cruz, FIOCRUZ, unidade Rondônia, Porto Velho, RO, Brazil
| | | | - Sibele Andrade Roberto
- Plataforma Bi-institucional de Medicina Translacional, Fundação Oswaldo Cruz-USP, Ribeirão Preto, SP, Brazil
| | - Marcos Barros Luiz
- Instituto Federal de Rondônia Campus Guajará-Mirim, IFRO, Guajará-Mirim, RO, Brazil
| | - Livia Coelho de Assis
- Programa de Pós-Graduação em Biologia Celular e Molecular, Instituto Oswaldo Cruz, IOC, Rio de Janeiro, RJ, Brazil; Laboratório Multiusuário de Pesquisa e Desenvolvimento, Fundação Oswaldo Cruz, Fiocruz unidade Ceará, Eusebio, CE, Brazil
| | - Anna Carolina M Marinho
- Laboratório Multiusuário de Pesquisa e Desenvolvimento, Fundação Oswaldo Cruz, Fiocruz unidade Ceará, Eusebio, CE, Brazil; Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal do Ceará, Fortaleza, CE, Brazil
| | - Luiz Felipe Lemes de Araujo
- Plataforma Bi-institucional de Medicina Translacional, Fundação Oswaldo Cruz-USP, Ribeirão Preto, SP, Brazil; Programa de Pós-Graduação em Imunologia Básica e Aplicada, Universidade de São Paulo, USP, Ribeirão Preto, SP, Brazil
| | - Rafael de Souza Pontes
- Plataforma Bi-institucional de Medicina Translacional, Fundação Oswaldo Cruz-USP, Ribeirão Preto, SP, Brazil; Programa de Pós-Graduação em Imunologia Básica e Aplicada, Universidade de São Paulo, USP, Ribeirão Preto, SP, Brazil
| | - Rodrigo Guerino Stabeli
- Plataforma Bi-institucional de Medicina Translacional, Fundação Oswaldo Cruz-USP, Ribeirão Preto, SP, Brazil
| | - Carla Freire Celedonio Fernandes
- Programa de Pós-Graduação em Biologia Celular e Molecular, Instituto Oswaldo Cruz, IOC, Rio de Janeiro, RJ, Brazil; Laboratório Multiusuário de Pesquisa e Desenvolvimento, Fundação Oswaldo Cruz, Fiocruz unidade Ceará, Eusebio, CE, Brazil; Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal do Ceará, Fortaleza, CE, Brazil
| | - Soraya Dos Santos Pereira
- Laboratório de Engenharia de Anticorpos, Fundação Oswaldo Cruz, FIOCRUZ, unidade Rondônia, Porto Velho, RO, Brazil; Programa de Pós-Graduação em Biologia Celular e Molecular, Instituto Oswaldo Cruz, IOC, Rio de Janeiro, RJ, Brazil; Programa de Pós-graduação em Biologia Experimental, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil.
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Sessions Z, Bobrowski T, Martin HJ, Beasley JMT, Kothari A, Phares T, Li M, Alves VM, Scotti MT, Moorman NJ, Baric R, Tropsha A, Muratov EN. Praemonitus praemunitus: can we forecast and prepare for future viral disease outbreaks? FEMS Microbiol Rev 2023; 47:fuad048. [PMID: 37596064 PMCID: PMC10532129 DOI: 10.1093/femsre/fuad048] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 07/04/2023] [Accepted: 08/17/2023] [Indexed: 08/20/2023] Open
Abstract
Understanding the origins of past and present viral epidemics is critical in preparing for future outbreaks. Many viruses, including SARS-CoV-2, have led to significant consequences not only due to their virulence, but also because we were unprepared for their emergence. We need to learn from large amounts of data accumulated from well-studied, past pandemics and employ modern informatics and therapeutic development technologies to forecast future pandemics and help minimize their potential impacts. While acknowledging the complexity and difficulties associated with establishing reliable outbreak predictions, herein we provide a perspective on the regions of the world that are most likely to be impacted by future outbreaks. We specifically focus on viruses with epidemic potential, namely SARS-CoV-2, MERS-CoV, DENV, ZIKV, MAYV, LASV, noroviruses, influenza, Nipah virus, hantaviruses, Oropouche virus, MARV, and Ebola virus, which all require attention from both the public and scientific community to avoid societal catastrophes like COVID-19. Based on our literature review, data analysis, and outbreak simulations, we posit that these future viral epidemics are unavoidable, but that their societal impacts can be minimized by strategic investment into basic virology research, epidemiological studies of neglected viral diseases, and antiviral drug discovery.
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Affiliation(s)
- Zoe Sessions
- Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, 301 Pharmacy Ln, Chapel Hill, NC 27599, United States
| | - Tesia Bobrowski
- Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, 301 Pharmacy Ln, Chapel Hill, NC 27599, United States
| | - Holli-Joi Martin
- Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, 301 Pharmacy Ln, Chapel Hill, NC 27599, United States
| | - Jon-Michael T Beasley
- Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, 301 Pharmacy Ln, Chapel Hill, NC 27599, United States
| | - Aneri Kothari
- Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, 301 Pharmacy Ln, Chapel Hill, NC 27599, United States
| | - Trevor Phares
- Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, 301 Pharmacy Ln, Chapel Hill, NC 27599, United States
- School of Chemistry, University of Louisville, 2320 S Brook St, Louisville, KY 40208, United States
| | - Michael Li
- Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, 301 Pharmacy Ln, Chapel Hill, NC 27599, United States
| | - Vinicius M Alves
- Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, 301 Pharmacy Ln, Chapel Hill, NC 27599, United States
| | - Marcus T Scotti
- Department of Pharmaceutical Sciences, Federal University of Paraiba, Campus I Lot. Cidade Universitaria, PB, 58051-900, Brazil
| | - Nathaniel J Moorman
- Department of Microbiology and Immunology, University of North Carolina, 116 Manning Drive, Chapel Hill, NC 27599, United States
| | - Ralph Baric
- Department of Epidemiology, University of North Carolina, 401 Pittsboro St, Chapel Hill, NC 27599, United States
| | - Alexander Tropsha
- Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, 301 Pharmacy Ln, Chapel Hill, NC 27599, United States
| | - Eugene N Muratov
- Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina, 301 Pharmacy Ln, Chapel Hill, NC 27599, United States
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Winder N, Gohar S, Muthana M. Norovirus: An Overview of Virology and Preventative Measures. Viruses 2022; 14:v14122811. [PMID: 36560815 PMCID: PMC9781483 DOI: 10.3390/v14122811] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 12/05/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Norovirus (NoV) is an enteric non-enveloped virus which is the leading cause of gastroenteritis across all age groups. It is responsible for around 200,000 deaths annually and outbreaks are common in small communities such as educational and care facilities. 40% of all NoV outbreaks occur in long-term and acute-care facilities, forming the majority of outbreaks. Nosocomial settings set ideal environments for ease of transmission, especially due to the presence of immunocompromised groups. It is estimated to cost global economies around £48 billion a year, making it a global issue. NoV is transmitted via the faecal-oral route and infection with it results in asymptomatic cases or gastrointestinal disease. It has high mutational rates and this allows for new variants to emerge and be more resistant. The classification system available divides NoV into 10 genogroups and 49 genotypes based on whole amino acid sequencing of VP1 capsid protein and partial sequencing of RdRp, respectively. The most predominant genotypes which cause gastroenteritis in humans include GI.1 and GII.4, where GII.4 is responsible for more extreme clinical implications such as hospitalisation. In addition, GII.4 has been responsible for 6 pandemic strains, the last of which is the GII.4 Sydney (2012) variant. In recent years, the successful cultivation of HuNoV was reported in stem cell-derived human intestinal enteroids (HIEs), which promises to assist in giving a deeper understanding of its underlying mechanisms of infection and the development of more personalized control measures. There are no specific control measures against NoV, therefore common practices are used against it such as hand washing. No vaccine is available, but the HIL-214 candidate passed clinical phase 2b and shows promise.
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Virus Association with Gastric Inflammation and Cancer: An Updated Overview. JOURNAL OF MEDICAL MICROBIOLOGY AND INFECTIOUS DISEASES 2022. [DOI: 10.52547/jommid.10.4.163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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He S, Nahhas AF, Habib AH, Alshehri MA, Alshamrani S, Asiri SA, Alnamshan MM, Helmi N, Al-Dhuayan I, Almulhim J, Alharbi AM, Su D, Kumari A, Rahaman A. Identification of compelling inhibitors of human norovirus 3CL protease to combat gastroenteritis: A structure-based virtual screening and molecular dynamics study. Front Chem 2022; 10:1034911. [PMID: 36247661 PMCID: PMC9561104 DOI: 10.3389/fchem.2022.1034911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 09/12/2022] [Indexed: 11/13/2022] Open
Abstract
Human noroviruses (NV) are the most prevalent cause of sporadic and pandemic acute gastroenteritis. NV infections cause substantial morbidity and death globally, especially amongst the aged, immunocompromised individuals, and children. There are presently no authorized NV vaccines, small-molecule therapies, or prophylactics for humans. NV 3 C L protease (3CLP) has been identified as a promising therapeutic target for anti-NV drug development. Herein, we employed a structure-based virtual screening method to screen a library of 700 antiviral compounds against the active site residues of 3CLP. We report three compounds, Sorafenib, YM201636, and LDC4297, that were revealed to have a higher binding energy (BE) value with 3CLP than the control (Dipeptidyl inhibitor 7) following a sequential screening, in-depth molecular docking and visualization, physicochemical and pharmacological property analysis, and molecular dynamics (MD) study. Sorafenib, YM201636, and LDC4297 had BEs of -11.67, -10.34, and -9.78 kcal/mol with 3CLP, respectively, while control had a BE of -6.38 kcal/mol. Furthermore, MD simulations of the two best compounds and control were used to further optimize the interactions, and a 100 ns MD simulation revealed that they form stable complexes with 3CLP. The estimated physicochemical, drug-like, and ADMET properties of these hits suggest that they might be employed as 3CLP inhibitors in the management of gastroenteritis. However, wet lab tests are a prerequisite to optimize them as NV 3CLP inhibitors.
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Affiliation(s)
- Shan He
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou, China
- Institute for Nano Scale and Technology, College of Science and Engineering, Flinders University, Adelaide, SA, Australia
- Suzhou Ultra-Water-Cleaning Tech, Pty, Ltd., Suzhou, Jiangsu, China
| | - Alaa F. Nahhas
- Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Alaa Hamed Habib
- Department of Physiology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mohammed Ali Alshehri
- Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, Najran University, Najran, Saudi Arabia
| | - Saleh Alshamrani
- Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, Najran University, Najran, Saudi Arabia
| | - Saeed A. Asiri
- Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, Najran University, Najran, Saudi Arabia
| | - Mashael M. Alnamshan
- Department of Biology, College of Science, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Nawal Helmi
- Department of Biochemistry, College of Science, University of Jeddah, Jeddah, Saudi Arabia
- Department of Medical Laboratory Technology, College of Applied Medical Sciences, University of Jeddah, Jeddah, Saudi Arabia
| | - Ibtesam Al-Dhuayan
- Department of Biology, College of Science, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Jawaher Almulhim
- Department of Biological Sciences, King Faisal University, Alahsa, Saudi Arabia
| | - Ahmed M. Alharbi
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, University of Hail, Hail, Saudi Arabia
| | - Dongxiao Su
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou, China
- *Correspondence: Dongxiao Su, ; Ankita Kumari, ; Abdul Rahaman,
| | - Ankita Kumari
- School of Food Science and Engineering, South china University of Technology, Guangzhou, China
- *Correspondence: Dongxiao Su, ; Ankita Kumari, ; Abdul Rahaman,
| | - Abdul Rahaman
- School of Food Science and Engineering, South china University of Technology, Guangzhou, China
- *Correspondence: Dongxiao Su, ; Ankita Kumari, ; Abdul Rahaman,
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Jang H, Lee C, Hwang Y, Lee SJ. Concanavalin A: coordination diversity to xenobiotic metal ions and biological consequences. Dalton Trans 2021; 50:17817-17831. [PMID: 34806716 DOI: 10.1039/d1dt03501k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The binding ability of lectins has gained attention owing to the carbohydrate-specific interactions of these proteins. Such interactions can be applied to diverse fields of biotechnology, including the detection, isolation, and concentration of biological target molecules. The physiological aspects of the lectin concanavalin A (ConA) have been intensively studied through structural and functional investigations. X-ray crystallography studies have proven that ConA has two β-sheets and a short α-helix and that it exists in the form of a metalloprotein containing Mn2+ and Ca2+. These heterometals are coordinated with side chains located in a metal-coordinated domain (MCD), and they affect the structural environment in the carbohydrate-binding domain (CBD), which interacts with carbohydrates through hydrogen bonds. Recent studies have shown that ConA can regulate biophysical interactions with glycoproteins in virus envelopes because it specifically interacts with diverse polysaccharides through its CBD (Tyr, Asn, Asp, and Arg residues positioned next to the MCD). Owing to their protein-protein interaction abilities, ConA can form diverse self-assembled complexes including monomers, dimers, trimers, and tetramers, thus affording unique results in different applications. In this regard, herein, we present a review of the structural modifications in ConA through metal-ion coordination and their effect on complex formation. In recent approaches, ConA has been applied for viral protein detection, on the basis of the interactions of ConA. These aspects indicate that lectins should be thoroughly investigated with respect to their biophysical interactions, for avoiding unexpected changes in their interaction abilities.
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Affiliation(s)
- Hara Jang
- Department of Chemistry and Institute for Molecular Biology and Genetics, Jeonbuk National University, Jeonju 54896, Republic of Korea.
| | - Chaemin Lee
- Department of Chemistry and Institute for Molecular Biology and Genetics, Jeonbuk National University, Jeonju 54896, Republic of Korea.
| | - Yunha Hwang
- Department of Chemistry and Institute for Molecular Biology and Genetics, Jeonbuk National University, Jeonju 54896, Republic of Korea.
| | - Seung Jae Lee
- Department of Chemistry and Institute for Molecular Biology and Genetics, Jeonbuk National University, Jeonju 54896, Republic of Korea.
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10
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Fenizia C, Ibba SV, Vanetti C, Strizzi S, Rossignol JF, Biasin M, Trabattoni D, Clerici M. The Modulation of Cholesterol Metabolism Is Involved in the Antiviral Effect of Nitazoxanide. Infect Dis Rep 2021; 13:636-644. [PMID: 34287319 PMCID: PMC8293206 DOI: 10.3390/idr13030060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/09/2021] [Accepted: 07/11/2021] [Indexed: 11/19/2022] Open
Abstract
We previously investigated the role of Nitazoxanide (NTZ), a thiazolide endowed with antiviral and antiparasitic activity, in HIV-1 infection. NTZ treatment in primary isolated PBMCs was able to reduce HIV-1 infection in vitro by inducing the expression of a number of type-I interferon-stimulated genes. Among them, NTZ was able to induce cholesterol-25-hydroxylase (CH25H), which is involved in cholesterol metabolism. In the present study, we wanted to deepen our knowledge about the antiviral mechanism of action of NTZ. Indeed, by inducing CH25H, which catalyzes the formation of 25-hydroxycholesterol from cholesterol, NTZ treatment repressed cholesterol biosynthetic pathways and promoted cholesterol mobilization and efflux from the cell. Such effects were even more pronounced upon stimulation with FLU antigens in combination. It is already well known how lipid metabolism and virus replication are tightly interconnected; thus, it is not surprising that the antiviral immune response employs genes related to cholesterol metabolism. Indeed, NTZ was able to modulate cholesterol metabolism in vitro and, by doing so, enhance the antiviral response. These results give us the chance to speculate about the suitability of NTZ as adjuvant for induction of specific natural immunity. Moreover, the putative application of NTZ to alimentary-related diseases should be investigated.
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Affiliation(s)
- Claudio Fenizia
- Department of Pathophysiology and Transplantation, University of Milan, Via F. Sforza 35, 20122 Milan, Italy; (C.F.); (C.V.)
- Department of Biomedical and Clinical Sciences, University of Milan, Via G.B. Grassi 74, 20157 Milan, Italy; (S.V.I.); (S.S.); (M.B.); (D.T.)
| | - Salomè Valentina Ibba
- Department of Biomedical and Clinical Sciences, University of Milan, Via G.B. Grassi 74, 20157 Milan, Italy; (S.V.I.); (S.S.); (M.B.); (D.T.)
| | - Claudia Vanetti
- Department of Pathophysiology and Transplantation, University of Milan, Via F. Sforza 35, 20122 Milan, Italy; (C.F.); (C.V.)
- Department of Biomedical and Clinical Sciences, University of Milan, Via G.B. Grassi 74, 20157 Milan, Italy; (S.V.I.); (S.S.); (M.B.); (D.T.)
| | - Sergio Strizzi
- Department of Biomedical and Clinical Sciences, University of Milan, Via G.B. Grassi 74, 20157 Milan, Italy; (S.V.I.); (S.S.); (M.B.); (D.T.)
| | | | - Mara Biasin
- Department of Biomedical and Clinical Sciences, University of Milan, Via G.B. Grassi 74, 20157 Milan, Italy; (S.V.I.); (S.S.); (M.B.); (D.T.)
| | - Daria Trabattoni
- Department of Biomedical and Clinical Sciences, University of Milan, Via G.B. Grassi 74, 20157 Milan, Italy; (S.V.I.); (S.S.); (M.B.); (D.T.)
| | - Mario Clerici
- Department of Pathophysiology and Transplantation, University of Milan, Via F. Sforza 35, 20122 Milan, Italy; (C.F.); (C.V.)
- IRCCS Fondazione Don Carlo Gnocchi, Via A. Capecelatro 66, 20148 Milan, Italy
- Correspondence: ; Tel.: +39-02-5031-9678
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11
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Kondapi DS, Ramani S, Estes MK, Atmar RL, Okhuysen PC. Norovirus in Cancer Patients: A Review. Open Forum Infect Dis 2021; 8:ofab126. [PMID: 34189156 PMCID: PMC8232388 DOI: 10.1093/ofid/ofab126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 03/10/2021] [Indexed: 12/15/2022] Open
Abstract
Norovirus (NoV) is the leading cause of viral-related diarrhea in cancer patients, in whom it can be chronic, contributing to decreased quality of life, interruption of cancer care, malnutrition, and altered mucosal barrier function. Immunosuppressed cancer patients shed NoV for longer periods of time than immunocompetent hosts, favoring quasispecies development and emergence of novel NoV variants. While nucleic acid amplification tests (NAATs) for NoV diagnosis have revolutionized our understanding of NoV burden of disease, not all NAATs provide information on viral load or infecting genotype. There is currently no effective antiviral or vaccine for chronic NoV infections. Screening for inhibitors of NoV replication in intestinal organoid culture models and creation of NoV-specific adoptive T cells are promising new strategies to develop treatments for chronic NoV in immunosuppressed patients. Herein we summarize data on the epidemiology, clinical manifestations, diagnostic challenges, and treatment of NoV infection in patients with cancer.
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Affiliation(s)
- Divya Samantha Kondapi
- Department of Infectious Diseases, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
- Section of Infectious Diseases, Baylor College of Medicine, Houston, Texas, USA
| | - Sasirekha Ramani
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Mary K Estes
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Robert L Atmar
- Section of Infectious Diseases, Baylor College of Medicine, Houston, Texas, USA
| | - Pablo C Okhuysen
- Infection Control and Employee Health, Division of Internal Medicine, Department of Infectious Diseases, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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12
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Gras J, Abdel-Nabey M, Dupont A, Le Goff J, Molina JM, Peraldi MN. Clinical characteristics, risk factors and outcome of severe Norovirus infection in kidney transplant patients: a case-control study. BMC Infect Dis 2021; 21:351. [PMID: 33858369 PMCID: PMC8048172 DOI: 10.1186/s12879-021-06062-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 04/05/2021] [Indexed: 12/20/2022] Open
Abstract
Background Human Norovirus (HuNoV) has recently been identified as a major cause of diarrhea among kidney transplant recipients (KTR). Data regarding risk factors associated with the occurrence of HuNoV infection, and its long-term impact on kidney function are lacking. Methods We conducted a retrospective case-control study including all KTR with a diagnosis of HuNoV diarrhea. Each case was matched to a single control according to age and date of transplantation, randomly selected among our KTR cohort and who did not develop HuNoV infection. Risk factors associated with HuNoV infection were identified using conditional logistic regression, and survival was estimated using Kaplan-Meier estimator. Results From January 2012 to April 2018, 72 cases of NoV diarrhea were identified among 985 new KT, leading to a prevalence of HuNoV infection of 7.3%. Median time between kidney transplantation and diagnosis was 46.5 months (Inter Quartile Range [IQR]:17.8–81.5), and the median duration of symptoms 40 days (IQR: 15–66.2). Following diagnosis, 93% of the cases had a reduction of immunosuppression. During follow-up, de novo Donor Specific Antibody (DSA) were observed in 8 (9%) cases but none of the controls (p = 0.01). Acute rejection episodes were significantly more frequent among cases (13.8% versus 4.2% in controls; p = 0,03), but there was no difference in serum creatinine level at last follow-up between the two groups (p = 0.08). Pre-transplant diabetes and lymphopenia below 1000/mm3 were identified as risks factors for HuNoV infection in multivariate analysis. Conclusion HuNoV infection is a late-onset and prolonged infection among KTR. The current management, based on the reduction of immunosuppressive treatment, is responsible for the appearance of de novo DSA and an increase in acute rejection episodes.
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Affiliation(s)
- Julien Gras
- Infectious Diseases Department, APHP, Saint-Louis Hospital, Paris, France. .,INSERM U944, "Cellular Biology of Viral Interactions" Team, Université de Paris, Paris, France.
| | - Moustafa Abdel-Nabey
- Nephrology and Kidney Transplant Department, APHP Saint Louis Hospital, Paris, France
| | - Axelle Dupont
- Biostatistics and Medical IT Department, APHP- Saint-Louis Hospital, Paris ECSTRA Team, UMR 1153 INSERM, Université de Paris, Paris, France
| | - Jérôme Le Goff
- Virology Department, APHP, Saint-Louis Hospital, Paris, France
| | - Jean-Michel Molina
- Infectious Diseases Department, APHP, Saint-Louis Hospital, Paris, France.,INSERM U944, "Cellular Biology of Viral Interactions" Team, Université de Paris, Paris, France
| | - Marie Noëlle Peraldi
- INSERM U944, "Cellular Biology of Viral Interactions" Team, Université de Paris, Paris, France.,Nephrology and Kidney Transplant Department, APHP Saint Louis Hospital, Paris, France
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13
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Esposito S, Principi N. Norovirus Vaccine: Priorities for Future Research and Development. Front Immunol 2020; 11:1383. [PMID: 32733458 PMCID: PMC7358258 DOI: 10.3389/fimmu.2020.01383] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 05/29/2020] [Indexed: 12/25/2022] Open
Abstract
Soon after its identification, norovirus (NoV) has been indicated as one of the most common causes of outbreaks of acute gastroenteritis (AGE) and sporadic acute diarrhea episodes in subjects of any age. In 2016 the World Health Organization stated that the development of a NoV vaccine should be considered an absolute priority. Unfortunately, the development of an effective NoV vaccine has proven extremely difficult, and only in recent years, some preparations have been tested in humans in advanced clinical trials. In this paper, reasons that justify efforts to develop a NoV vaccine, difficulties encountered during NoV vaccine development, and NoV vaccine candidates will be discussed. In recent years, identification of some NoV antigens that alone or in combination with other viral antigens can induce a potentially protective immune response has led to the development of a large series of preparations that seem capable of coping with the problems related to NoV infection. Epidemiological and immunological studies have shown that multivalent vaccines, including both GI and GII NoV, are the only solution to induce sufficiently broad protection. However, even if the road to formulation of an effective and safe NoV vaccine seems to be definitively traced, many problems still need to be solved before the total burden of NoV infections can be adequately controlled. Whether currently available vaccines are able to protect against all the heterologous NoV strains and the variants of the most common serotypes that frequently emerge and cause outbreaks must be defined. Moreover, as performed clinical trials have mainly enrolled adults, it is mandatory to know whether vaccines are effective in all age groups, including younger children. Finally, we must know the immune response of immunocompromised patients and the duration of protection induced by NoV vaccines. Only when all these problems have been solved will it be possible to establish an effective immunization schedule against NoV infection and calculate whether systematic vaccination can be cost effective.
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Affiliation(s)
- Susanna Esposito
- Pediatric Clinic, Department of Medicine and Surgery, Pietro Barilla Children's Hospital, University of Parma, Parma, Italy
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14
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Quantifying the roles of vomiting, diarrhea, and residents vs. staff in norovirus transmission in U.S. nursing home outbreaks. PLoS Comput Biol 2020; 16:e1007271. [PMID: 32210423 PMCID: PMC7135310 DOI: 10.1371/journal.pcbi.1007271] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 04/06/2020] [Accepted: 02/21/2020] [Indexed: 12/16/2022] Open
Abstract
The role of individual case characteristics, such as symptoms or demographics, in norovirus transmissibility is poorly understood. Six nursing home norovirus outbreaks occurring in South Carolina, U.S. from 2014 to 2016 were examined. We aimed to quantify the contribution of symptoms and other case characteristics in norovirus transmission using the reproduction number (REi) as an estimate of individual case infectivity and to examine how transmission changes over the course of an outbreak. Individual estimates of REi were calculated using a maximum likelihood procedure to infer the average number of secondary cases generated by each case. The associations between case characteristics and REi were estimated using a weighted multivariate mixed linear model. Outbreaks began with one to three index case(s) with large estimated REi’s (range: 1.48 to 8.70) relative to subsequent cases. Of the 209 cases, 155 (75%) vomited, 164 (79%) had diarrhea, and 158 (76%) were nursing home residents (vs. staff). Cases who vomited infected 2.12 (95% CI: 1.68, 2.68) times the number of individuals as non-vomiters, cases with diarrhea infected 1.39 (95% CI: 1.03, 1.87) times the number of individuals as cases without diarrhea, and resident-cases infected 1.53 (95% CI: 1.15, 2.02) times the number of individuals as staff-cases. Index cases tended to be residents (vs. staff) who vomited and infected considerably more secondary cases compared to non-index cases. Results suggest that individuals, particularly residents, who vomit are more infectious and tend to drive norovirus transmission in U.S. nursing home norovirus outbreaks. While diarrhea also plays a role in norovirus transmission, it is to a lesser degree than vomiting in these settings. Results lend support for prevention and control measures that focus on cases who vomit, particularly if those cases are residents. The majority of all norovirus outbreaks reported to the CDC occur in long-term care facilities (LTCFs), including nursing homes, where older residents are at risk for more severe or prolonged infection. Because there is currently no publicly available norovirus vaccine, sound control measures are key to controlling norovirus outbreaks, but there is little evidence that standard control measures are effective in reducing the size and/or duration of LTCF norovirus outbreaks. Hence, studies leading to a better understanding of disease spread and prevention of additional cases, and thus more effective control measures, are needed. To this end, we aimed to quantify factors associated with norovirus transmission and to examine how transmission changes over the course of an outbreak. We show that vomiting and, to a lesser extent, diarrhea are critical in initiating and sustaining norovirus transmission in U.S. nursing home norovirus outbreaks. We also show that nursing home residents, rather than staff, are the primary drivers of transmission. Results suggest that control measures focusing on cases who vomit, particularly if those cases are residents, would be most effective at curtailing norovirus transmission in these settings.
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Chukwu MO, Abia ALK, Ubomba-Jaswa E, Dewar JB, Obi C. Mixed Aetiology of Diarrhoea in Infants Attending Clinics in the North-West Province of South Africa: Potential for Sub-Optimal Treatment. Pathogens 2020; 9:E198. [PMID: 32155961 PMCID: PMC7157715 DOI: 10.3390/pathogens9030198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 11/28/2019] [Accepted: 12/01/2019] [Indexed: 11/17/2022] Open
Abstract
Routine diagnostic methods for the aetiologic agents of diarrhoea in most developing countries are usually not sensitive enough, leading to under-diagnosis. Thus, this study investigated possible mixed diarrhoeal aetiology by using cultures and real-time polymerase chain reactions (PCR) in children younger than four years old in the Northwest Province, South Africa. In total, 505 stool samples were collected from symptomatic and asymptomatic children who were attending three clinics and the Brits hospital in Madibeng District, between September 2016 and December 2017. Rotavirus, norovirus, Campylobacter, Arcobacter, and diarrhoeagenic Escherichia coli (DEC) were targeted. Campylobacter spp. (24.6%), Arcobacter (15.8%) and DEC (19.6%) were detected using PCR; only Campylobacter spp. (29.7%) and DEC (26.9%) were detected through the culture. Campylobacter jejuni (36%), Campylobacter coli (28%), Campylobacter upsalensis (12%), and Arcobacter butzleri (15.8%) were the only spp. of Campylobacter and Arcobacter identified. The eaeA gene (31.4%) of enteropathogenic E. coli/enterohaemorrhagic E. coli (EPEC/EHEC) was the most prevalent DEC virulence gene (VG) identified. Rotavirus and norovirus were detected at 23.4% and 20%, respectively. Mixed viral aetiology (7.3%) and the co-infection of A. butzleri and Campylobacter (49%) were recorded. A mixed bacterial-viral aetiology was observed in 0.6% of the specimens. Sensitive diagnostic procedures like PCR should be considered to provide the best treatment to children experiencing diarrhoea.
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Affiliation(s)
- Martina O. Chukwu
- Department of Life Sciences, College of Agriculture and Environmental Sciences, University of South Africa, Corner Christiaan De wet and Pioneer Avenue, Florida Park, Roodepoort 1724, Gauteng, South Africa;
| | - Akebe Luther King Abia
- Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa;
| | - Eunice Ubomba-Jaswa
- Department of Biotechnology, University of Johannesburg, 37 Nind Street, Doornfontein 2094, Gauteng, South Africa;
- Water Research Commission, Lynnwood Bridge Office Park, Bloukrans Building, 4 Daventry Street, Lynnwood Manor, Pretoria 0081, South Africa
| | - John Barr Dewar
- Department of Life Sciences, College of Agriculture and Environmental Sciences, University of South Africa, Corner Christiaan De wet and Pioneer Avenue, Florida Park, Roodepoort 1724, Gauteng, South Africa;
| | - C.L. Obi
- School of Science and Technology, Sefako Makgatho Health Science University, Ga-Rankuwa 0208, South Africa;
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A new antiviral scaffold for human norovirus identified with computer-aided approaches on the viral polymerase. Sci Rep 2019; 9:18413. [PMID: 31804593 PMCID: PMC6895199 DOI: 10.1038/s41598-019-54903-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 11/20/2019] [Indexed: 12/20/2022] Open
Abstract
Human norovirus is the leading cause of acute gastroenteritis worldwide, affecting every year 685 million people. In about one third of cases, this virus affects children under five years of age, causing each year up to 200,000 child deaths, mainly in the developing countries. Norovirus outbreaks are associated with very significant economic losses, with an estimated societal cost of 60 billion dollars per year. Despite the marked socio-economic consequences associated, no therapeutic options or vaccines are currently available to treat or prevent this infection. One promising target to identify new antiviral agents for norovirus is the viral polymerase, which has a pivotal role for the viral replication and lacks closely homologous structures in the host. Starting from the scaffold of a novel class of norovirus polymerase inhibitors recently discovered in our research group with a computer-aided method, different new chemical modifications were designed and carried out, with the aim to identify improved agents effective against norovirus replication in cell-based assays. While different new inhibitors of the viral polymerase were found, a further computer-aided ligand optimisation approach led to the identification of a new antiviral scaffold for norovirus, which inhibits human norovirus replication at low-micromolar concentrations.
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Angarone M, Snydman DR. Diagnosis and management of diarrhea in solid-organ transplant recipients: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice. Clin Transplant 2019; 33:e13550. [PMID: 30913334 DOI: 10.1111/ctr.13550] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 03/19/2019] [Indexed: 12/30/2022]
Abstract
These guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of diarrhea in the pre- and post-transplant period. Diarrhea in an organ transplant recipient may result in significant morbidity including dehydration, increased toxicity of medications, and rejection. Transplant recipients are affected by a wide range of etiologies of diarrhea with the most common causes being Clostridioides (formerly Clostridium) difficile infection, cytomegalovirus, and norovirus. Other bacterial, viral, and parasitic causes can result in diarrhea but are far less common. Further, noninfectious causes including medication toxicity, inflammatory bowel disease, post-transplant lymphoproliferative disease, and malignancy can also result in diarrhea in the transplant population. Management of diarrhea in this population is directed at the cause of the diarrhea, instituting therapy where appropriate and maintaining proper hydration. Identification of the cause to the diarrhea needs to be timely and focused.
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Affiliation(s)
- Michael Angarone
- Division of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - David R Snydman
- Department of Medicine, The Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, Tufts University School of Medicine, Boston, Massachusetts
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Lee S, Liu H, Wilen CB, Sychev ZE, Desai C, Hykes BL, Orchard RC, McCune BT, Kim KW, Nice TJ, Handley SA, Baldridge MT, Amarasinghe GK, Virgin HW. A Secreted Viral Nonstructural Protein Determines Intestinal Norovirus Pathogenesis. Cell Host Microbe 2019; 25:845-857.e5. [PMID: 31130511 PMCID: PMC6622463 DOI: 10.1016/j.chom.2019.04.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 03/08/2019] [Accepted: 04/15/2019] [Indexed: 12/18/2022]
Abstract
Murine norovirus (MNoV) infects a low percentage of enteric tuft cells and can persist in these cells for months following acute infection. Both tuft-cell tropism and resistance to interferon-λ (IFN-λ)-mediated clearance during persistent infection requires the viral nonstructural protein 1/2 (NS1/2). We show that processing of NS1/2 yields NS1, an unconventionally secreted viral protein that is central for IFN-λ resistance. MNoV infection globally suppresses intestinal IFN-λ responses, which is attributable to secreted NS1. MNoV NS1 secretion is triggered by caspase-3 cleavage of NS1/2, and a secreted form of human NoV NS1 is also observed. NS1 secretion is essential for intestinal infection and resistance to IFN-λ in vivo. NS1 vaccination alone protects against MNoV challenge, despite the lack of induction of neutralizing anti-capsid antibodies previously shown to confer protection. Thus, despite infecting a low number of tuft cells, NS1 secretion allows MNoV to globally suppress IFN responses and promote persistence.
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Affiliation(s)
- Sanghyun Lee
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Hejun Liu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Craig B Wilen
- Departments of Laboratory Medicine and Immunobiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Zoi E Sychev
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Chandni Desai
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Barry L Hykes
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Robert C Orchard
- Department of Immunology, the University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Broc T McCune
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ki-Wook Kim
- Department of Pharmacology and Center for Stem Cell and Regenerative Medicine, University of Illinois College of Medicine, Chicago, IL 60612, USA
| | - Timothy J Nice
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
| | - Scott A Handley
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Megan T Baldridge
- Department of Medicine, Division of Infectious Diseases, Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Herbert W Virgin
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Enosi Tuipulotu D, Fumian TM, Netzler NE, Mackenzie JM, White PA. The Adenosine Analogue NITD008 has Potent Antiviral Activity against Human and Animal Caliciviruses. Viruses 2019; 11:v11060496. [PMID: 31151251 PMCID: PMC6631109 DOI: 10.3390/v11060496] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 05/24/2019] [Accepted: 05/25/2019] [Indexed: 12/27/2022] Open
Abstract
The widespread nature of calicivirus infections globally has a substantial impact on the health and well-being of humans and animals alike. Currently, the only vaccines approved against caliciviruses are for feline and rabbit-specific members of this group, and thus there is a growing effort towards the development of broad-spectrum antivirals for calicivirus infections. In this study, we evaluated the antiviral activity of the adenosine analogue NITD008 in vitro using three calicivirus model systems namely; feline calicivirus (FCV), murine norovirus (MNV), and the human norovirus replicon. We show that the nucleoside analogue (NA), NITD008, has limited toxicity and inhibits calicivirus replication in all three model systems with EC50 values of 0.94 μM, 0.91 µM, and 0.21 µM for MNV, FCV, and the Norwalk replicon, respectively. NITD008 has a similar level of potency to the most well-studied NA 2′-C-methylcytidine in vitro. Significantly, we also show that continual NITD008 treatment effectively cleared the Norwalk replicon from cells and treatment with 5 µM NITD008 was sufficient to completely prevent rebound. Given the potency displayed by NITD008 against several caliciviruses, we propose that this compound should be interrogated further to assess its effectiveness in vivo. In summary, we have added a potent NA to the current suite of antiviral compounds and provide a NA scaffold that could be further modified for therapeutic use against calicivirus infections.
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Affiliation(s)
- Daniel Enosi Tuipulotu
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Tulio M Fumian
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
- Laboratório de Virologia Comparada e Ambiental, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro 21040-900, Brazil.
| | - Natalie E Netzler
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Jason M Mackenzie
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VC 3010, Australia.
| | - Peter A White
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
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21
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Galasiti Kankanamalage AC, Weerawarna PM, Rathnayake AD, Kim Y, Mehzabeen N, Battaile KP, Lovell S, Chang KO, Groutas WC. Putative structural rearrangements associated with the interaction of macrocyclic inhibitors with norovirus 3CL protease. Proteins 2019; 87:579-587. [PMID: 30883881 DOI: 10.1002/prot.25682] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 02/12/2019] [Accepted: 03/13/2019] [Indexed: 12/17/2022]
Abstract
Human noroviruses are the primary cause of outbreaks of acute gastroenteritis worldwide. The problem is further compounded by the current lack of norovirus-specific antivirals or vaccines. Noroviruses have a single-stranded, positive sense 7 to 8 kb RNA genome which encodes a polyprotein precursor that is processed by a virus-encoded 3C-like cysteine protease (NV 3CLpro) to generate at least six mature nonstructural proteins. Processing of the polyprotein is essential for virus replication, consequently, NV 3CLpro has emerged as an attractive target for the discovery of norovirus therapeutics and prophylactics. We have recently described the structure-based design of macrocyclic transition state inhibitors of NV 3CLpro. In order to gain insight and understanding into the interaction of macrocyclic inhibitors with the enzyme, as well as probe the effect of ring size on pharmacological activity and cellular permeability, additional macrocyclic inhibitors were synthesized and high resolution cocrystal structures determined. The results of our studies tentatively suggest that the macrocyclic scaffold may hamper optimal binding to the active site by impeding concerted cross-talk between the S2 and S4 subsites.
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Affiliation(s)
| | | | | | - Yunjeong Kim
- Department of Diagnostic Medicine & Pathobiology, College of Veterinary Medicine, Kansas State University, Kansas
| | | | - Kevin P Battaile
- IMCA-CAT, Hauptman-Woodward Medical Research Institute, APS Argonne National Laboratory, Argonne, Illinois
| | - Scott Lovell
- Protein Structure Laboratory, The University of Kansas, Kansas
| | - Kyeong-Ok Chang
- Department of Diagnostic Medicine & Pathobiology, College of Veterinary Medicine, Kansas State University, Kansas
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22
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Ferla S, Netzler NE, Ferla S, Veronese S, Tuipulotu DE, Guccione S, Brancale A, White PA, Bassetto M. In silico screening for human norovirus antivirals reveals a novel non-nucleoside inhibitor of the viral polymerase. Sci Rep 2018. [PMID: 29515206 PMCID: PMC5841303 DOI: 10.1038/s41598-018-22303-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Human norovirus causes approximately 219,000 deaths annually, yet there are currently no antivirals available. A virtual screening of commercially available drug-like compounds (~300,000) was performed on the suramin and PPNDS binding-sites of the norovirus RNA-dependent RNA polymerase (RdRp). Selected compounds (n = 62) were examined for inhibition of norovirus RdRp activity using an in vitro transcription assay. Eight candidates demonstrated RdRp inhibition (>25% inhibition at 10 µM), which was confirmed using a gel-shift RdRp assay for two of them. The two molecules were identified as initial hits and selected for structure-activity relationship studies, which resulted in the synthesis of novel compounds that were examined for inhibitory activity. Five compounds inhibited human norovirus RdRp activity (>50% at 10 µM), with the best candidate, 54, demonstrating an IC50 of 5.6 µM against the RdRp and a CC50 of 62.8 µM. Combinational treatment of 54 and the known RdRp site-B inhibitor PPNDS revealed antagonism, indicating that 54 binds in the same binding pocket. Two RdRps with mutations (Q414A and R419A) previously shown to be critical for the binding of site-B compounds had no effect on inhibition, suggesting 54 interacts with distinct site-B residues. This study revealed the novel scaffold 54 for further development as a norovirus antiviral.
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Affiliation(s)
- Salvatore Ferla
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, United Kingdom.
| | - Natalie E Netzler
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Sebastiano Ferla
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, United Kingdom.,Dipartimento di Scienze del Farmaco, Università degli Studi di Catania, Catania, Italy
| | - Sofia Veronese
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, United Kingdom
| | - Daniel Enosi Tuipulotu
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Salvatore Guccione
- Dipartimento di Scienze del Farmaco, Università degli Studi di Catania, Catania, Italy
| | - Andrea Brancale
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, United Kingdom
| | - Peter A White
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Marcella Bassetto
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, United Kingdom
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23
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Human Norovirus NS3 Has RNA Helicase and Chaperoning Activities. J Virol 2018; 92:JVI.01606-17. [PMID: 29237842 DOI: 10.1128/jvi.01606-17] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 12/07/2017] [Indexed: 12/22/2022] Open
Abstract
RNA-remodeling proteins, including RNA helicases and chaperones, act to remodel RNA structures and/or protein-RNA interactions and are required for all processes involving RNAs. Although many viruses encode RNA helicases and chaperones, their in vitro activities and their roles in infected cells largely remain elusive. Noroviruses are a diverse group of positive-strand RNA viruses in the family Caliciviridae and constitute a significant and potentially fatal threat to human health. Here, we report that the protein NS3 encoded by human norovirus has both ATP-dependent RNA helicase activity that unwinds RNA helices and ATP-independent RNA-chaperoning activity that can remodel structured RNAs and facilitate strand annealing. Moreover, NS3 can facilitate viral RNA synthesis in vitro by norovirus polymerase. NS3 may therefore play an important role in norovirus RNA replication. Lastly, we demonstrate that the RNA-remodeling activity of NS3 is inhibited by guanidine hydrochloride, an FDA-approved compound, and, more importantly, that it reduces the replication of the norovirus replicon in cultured human cells. Altogether, these findings are the first to demonstrate the presence of RNA-remodeling activities encoded by Caliciviridae and highlight the functional significance of NS3 in the noroviral life cycle.IMPORTANCE Noroviruses are a diverse group of positive-strand RNA viruses, which annually cause hundreds of millions of human infections and over 200,000 deaths worldwide. For RNA viruses, cellular or virus-encoded RNA helicases and/or chaperones have long been considered to play pivotal roles in viral life cycles. However, neither RNA helicase nor chaperoning activity has been demonstrated to be associated with any norovirus-encoded proteins, and it is also unknown whether norovirus replication requires the participation of any viral or cellular RNA helicases/chaperones. We found that a norovirus protein, NS3, not only has ATP-dependent helicase activity, but also acts as an ATP-independent RNA chaperone. Also, NS3 can facilitate in vitro viral RNA synthesis, suggesting the important role of NS3 in norovirus replication. Moreover, NS3 activities can be inhibited by an FDA-approved compound, which also suppresses norovirus replicon replication in human cells, raising the possibility that NS3 could be a target for antinoroviral drug development.
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24
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Cardemil CV, Parashar UD, Hall AJ. Norovirus Infection in Older Adults: Epidemiology, Risk Factors, and Opportunities for Prevention and Control. Infect Dis Clin North Am 2017; 31:839-870. [PMID: 28911830 PMCID: PMC6546097 DOI: 10.1016/j.idc.2017.07.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Norovirus is the leading cause of acute gastroenteritis. In older adults, it is responsible for an estimated 3.7 million illnesses; 320,000 outpatient visits; 69,000 emergency department visits; 39,000 hospitalizations; and 960 deaths annually in the United States. Older adults are particularly at risk for severe outcomes, including prolonged symptoms and death. Long-term care facilities and hospitals are the most common settings for norovirus outbreaks in developed countries. Diagnostic platforms are expanding. Several norovirus vaccines in clinical trials have the potential to reap benefits. This review summarizes current knowledge on norovirus infection in older adults.
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Affiliation(s)
- Cristina V Cardemil
- Viral Gastroenteritis Branch (proposed), Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - Umesh D Parashar
- Viral Gastroenteritis Branch (proposed), Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Aron J Hall
- Viral Gastroenteritis Branch (proposed), Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
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25
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Karangwa CK, Parra GI, Bok K, Johnson JA, Levenson EA, Green KY. Sequential Gastroenteritis Outbreaks in a Single Year Caused by Norovirus Genotypes GII.2 and GII.6 in an Institutional Setting. Open Forum Infect Dis 2017; 4:ofx236. [PMID: 30349844 DOI: 10.1093/ofid/ofx236] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Background Norovirus is a leading cause of acute gastroenteritis worldwide. Improved diagnostic capability has been instrumental in the characterization of archival norovirus strains associated with gastroenteritis outbreaks that were investigated decades ago. One such investigation was that of 2 sequential gastroenteritis outbreaks that occurred in 1971 at the former Henryton State Hospital in Maryland. Approximately 40% of the resident population experienced clinical symptoms in both outbreaks, which occurred 11 months apart. Methods Stored stools and paired sera were re-analyzed to investigate the etiology of the 2 outbreaks. Results Different norovirus genotypes were identified as the etiological agents responsible for the illnesses, with GII.2 associated with the first outbreak and GII.6 with the second. The viruses were antigenically distinct as determined by analyses of hyperimmune sera raised against the corresponding virus-like particles in animals, as well as paired sera from infected individuals. Conclusions The observed antigenic differences were consistent with the failure of the GII.2 strain to provide cross-protective immunity to the GII.6 strain a few months later. An understanding of antigenic diversity among norovirus genotypes will be important in the design of norovirus vaccines.
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Affiliation(s)
- Consolee K Karangwa
- Caliciviruses Section, Laboratoryof Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, DHHS, Bethesda, Maryland
| | - Gabriel I Parra
- Division of Viral Products, Food and Drug Administration, DHHS, Silver Spring, Maryland
| | - Karin Bok
- National Vaccine Program Office, DHHS, Washington, DC
| | - Jordan A Johnson
- Caliciviruses Section, Laboratoryof Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, DHHS, Bethesda, Maryland
| | - Eric A Levenson
- Caliciviruses Section, Laboratoryof Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, DHHS, Bethesda, Maryland
| | - Kim Y Green
- Caliciviruses Section, Laboratoryof Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, DHHS, Bethesda, Maryland
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26
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Norovirus Escape from Broadly Neutralizing Antibodies Is Limited to Allostery-Like Mechanisms. mSphere 2017; 2:mSphere00334-17. [PMID: 29062895 PMCID: PMC5646240 DOI: 10.1128/msphere.00334-17] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/27/2017] [Indexed: 01/03/2023] Open
Abstract
The simplest and most common way for viruses to escape antibody neutralization is by mutating residues that are essential for antibody binding. Escape mutations are strongly selected for by their effect on viral fitness, which is most often related to issues of protein folding, particle assembly, and capsid function. The studies presented here demonstrated that a broadly neutralizing antibody to mouse norovirus binds to an exposed surface but that the only escape mutants that arose were distal to the antibody binding surface. To understand this finding, we performed an in silico analysis that suggested that those escape mutations blocked antibody binding by affecting structural plasticity. This kind of antigenic region—one that gives rise to broadly neutralizing antibodies but that the virus finds difficult to escape from—is therefore ideal for vaccine development. Ideal antiviral vaccines elicit antibodies (Abs) with broad strain recognition that bind to regions that are difficult to mutate for escape. Using 10 murine norovirus (MNV) strains and 5 human norovirus (HuNoV) virus-like particles (VLPs), we identified monoclonal antibody (MAb) 2D3, which broadly neutralized all MNV strains tested. Importantly, escape mutants corresponding to this antibody were very slow to develop and were distal to those raised against our previously studied antibody, A6.2. To understand the atomic details of 2D3 neutralization, we determined the cryo-electron microscopy (cryo-EM) structure of the 2D3/MNV1 complex. Interestingly, 2D3 binds to the top of the P domain, very close to where A6.2 binds, but the only escape mutations identified to date fall well outside the contact regions of both 2D3 and A6.2. To determine how mutations in distal residues could block antibody binding, we used molecular dynamics flexible fitting simulations of the atomic structures placed into the density map to examine the 2D3/MNV1 complex and these mutations. Our findings suggest that the escape mutant, V339I, may stabilize a salt bridge network at the P-domain dimer interface that, in an allostery-like manner, affects the conformational relaxation of the P domain and the efficiency of binding. They further highlight the unusual antigenic surface bound by MAb 2D3, one which elicits cross-reactive antibodies but which the virus is unable to alter to escape neutralization. These results may be leveraged to generate norovirus (NoV) vaccines containing broadly neutralizing antibodies. IMPORTANCE The simplest and most common way for viruses to escape antibody neutralization is by mutating residues that are essential for antibody binding. Escape mutations are strongly selected for by their effect on viral fitness, which is most often related to issues of protein folding, particle assembly, and capsid function. The studies presented here demonstrated that a broadly neutralizing antibody to mouse norovirus binds to an exposed surface but that the only escape mutants that arose were distal to the antibody binding surface. To understand this finding, we performed an in silico analysis that suggested that those escape mutations blocked antibody binding by affecting structural plasticity. This kind of antigenic region—one that gives rise to broadly neutralizing antibodies but that the virus finds difficult to escape from—is therefore ideal for vaccine development.
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27
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Lee S, Wilen CB, Orvedahl A, McCune BT, Kim KW, Orchard RC, Peterson ST, Nice TJ, Baldridge MT, Virgin HW. Norovirus Cell Tropism Is Determined by Combinatorial Action of a Viral Non-structural Protein and Host Cytokine. Cell Host Microbe 2017; 22:449-459.e4. [PMID: 28966054 PMCID: PMC5679710 DOI: 10.1016/j.chom.2017.08.021] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 07/19/2017] [Accepted: 08/29/2017] [Indexed: 01/24/2023]
Abstract
Cellular tropism during persistent viral infection is commonly conferred by the interaction of a viral surface protein with a host receptor complex. Norovirus, the leading global cause of gastroenteritis, can be persistently shed during infection, but its in vivo cellular tropism and tropism determinants remain unidentified. Using murine norovirus (MNoV), we determine that a small number of intestinal epithelial cells (IECs) serve as the reservoir for fecal shedding and persistence. The viral non-structural protein NS1, rather than a viral surface protein, determines IEC tropism. Expression of NS1 from a persistent MNoV strain is sufficient for an acute MNoV strain to target IECs and persist. In addition, interferon-lambda (IFN-λ) is a key host determinant blocking MNoV infection in IECs. The inability of acute MNoV to shed and persist is rescued in Ifnlr1-/- mice, suggesting that NS1 evades IFN-λ-mediated antiviral immunity. Thus, NS1 and IFN-λ interactions govern IEC tropism and persistence of MNoV.
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Affiliation(s)
- Sanghyun Lee
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Craig B Wilen
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Anthony Orvedahl
- Department of Pediatrics, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Broc T McCune
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Ki-Wook Kim
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Robert C Orchard
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Stefan T Peterson
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Timothy J Nice
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, USA
| | - Megan T Baldridge
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO, USA.
| | - Herbert W Virgin
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA.
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28
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Galasiti Kankanamalage AC, Kim Y, Rathnayake AD, Alliston KR, Butler MM, Cardinale SC, Bowlin TL, Groutas WC, Chang KO. Design, Synthesis, and Evaluation of Novel Prodrugs of Transition State Inhibitors of Norovirus 3CL Protease. J Med Chem 2017; 60:6239-6248. [DOI: 10.1021/acs.jmedchem.7b00497] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
| | - Yunjeong Kim
- Department
of Diagnostic Medicine & Pathobiology, Kansas State University
College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506, United States
| | - Athri D. Rathnayake
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, United States
| | - Kevin R. Alliston
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, United States
| | | | | | - Terry L. Bowlin
- Microbiotix, Inc., Worcester, Massachusetts 01605, United States
| | - William C. Groutas
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, United States
| | - Kyeong-Ok Chang
- Department
of Diagnostic Medicine & Pathobiology, Kansas State University
College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506, United States
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29
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Brown LAK, Clark I, Brown JR, Breuer J, Lowe DM. Norovirus infection in primary immune deficiency. Rev Med Virol 2017; 27:e1926. [DOI: 10.1002/rmv.1926] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 01/19/2017] [Accepted: 01/31/2017] [Indexed: 02/06/2023]
Affiliation(s)
| | - Ian Clark
- Department of Cellular Pathology; Royal Free London NHS Foundation Trust; London UK
| | - Julianne R. Brown
- Microbiology, Virology and Infection Control; Great Ormond Street Hospital for Children NHS Foundation Trust; London UK
- NIHR Biomedical Research Centre; Great Ormond Street Hospital for Children NHS Foundation Trust and University College; London UK
| | - Judith Breuer
- Division of Infection and Immunity; University College London; London UK
| | - David M. Lowe
- Institute of Immunity and Transplantation; University College London, Royal Free Campus; London UK
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30
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Norovirus Disease in Older Adults Living in Long-Term Care Facilities: Strategies for Management. CURRENT GERIATRICS REPORTS 2017; 6:26-33. [PMID: 29204334 DOI: 10.1007/s13670-017-0195-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Purpose of Review Noroviruses are the most common cause of gastroenteritis outbreaks in long-term care facility (LTCFs). This review summarizes the most up-to-date knowledge on norovirus infection in LTCFs with the aim of identifying potential strategies for management. Recent Findings LTCF residents are at greater risk of norovirus infection. Early identification of norovirus infection and prompt initiation of appropriate supportive therapy are required to reduce morbidity and mortality. Measures to prevent outbreaks and reduce the risk of norovirus infection in LTCFs include timely diagnosis and implementation of infection control interventions to limit virus transmission. Summary Current guidelines for prevention and control are based on generic principles of infection control. Real-time reverse transcription-quantitative polymerase chain reaction assays have been the gold standard for the rapid and sensitive detection of noroviruses. With the recent breakthroughs of human norovirus in vitro culture, doors are now opened to evaluate the efficacy of environmental disinfectants and hand hygiene options. Additionally, development of licensed vaccines against noroviruses may provide another important tool for infection prevention among high-risk individuals.
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31
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Gastañaduy AS, Bégué RE. Acute Gastroenteritis Viruses. Infect Dis (Lond) 2017. [PMCID: PMC7173516 DOI: 10.1016/b978-0-7020-6285-8.00162-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Acute diarrhea is the leading cause of morbidity and second commonest cause of mortality in children <5 years old worldwide. Most acute diarrheal illnesses are caused by viruses. Noroviruses are the commonest cause of diarrhea in all age groups combined, and rotaviruses are still the leading cause of diarrhea for children <5 years old. Transmission is mainly by the fecal–oral route through person-to-person contact, contaminated food and water. Most cases of viral diarrhea are mild and self-limiting, but severe cases occur, leading to dehydration and death. Repeated episodes lead to malnutrition. Most cases can be managed at home with oral rehydration solutions and feeding a regular diet. Vaccines will be the best preventive measure. Only rotavirus vaccines are available. Breast-feeding, vitamin A supplementation and zinc significantly reduce the frequency and/or severity of diarrhea.
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32
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Structure(s), function(s), and inhibition of the RNA-dependent RNA polymerase of noroviruses. Virus Res 2016; 234:21-33. [PMID: 28041960 PMCID: PMC7114559 DOI: 10.1016/j.virusres.2016.12.018] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 12/19/2016] [Accepted: 12/24/2016] [Indexed: 12/17/2022]
Abstract
This review summarizes current knowledge on the norovirus RdRp. Multiple X-ray structures of norovirus RdRp show important conformational changes. Norovirus RdRp recognizes specific promotor sequences to initiate RNA synthesis. Anti-HCV nucleoside analogs such as 2CM-C also inhibit Norovirus RdRp. Suramin and its analogs act as allosteric non-nucleoside polymerase inhibitors.
Noroviruses belong to the Caliciviridae family of single-stranded positive-sense RNA viruses. The genus Norovirus includes seven genogroups (designated GI-GVII), of which GI, GII and GIV infect humans. Human noroviruses are responsible for widespread outbreaks of acute gastroenteritis and represent one of the most common causes of foodborne illness. No vaccine or antiviral treatment options are available for norovirus infection. The RNA-dependent RNA polymerase (RdRp) of noroviruses is a key enzyme responsible for transcription and replication of the viral genome. Here, we review the progress made in understanding the structures and functions of norovirus RdRp and its use as a target for small molecule inhibitors. Crystal structures of the RdRp at different stages of substrate interaction have been determined, which shed light on its multi-step catalytic cycle. The in vitro assays and in vivo animal models that have been developed to identify and characterize inhibitors of norovirus RdRp are also summarized, followed by an update on the current antiviral research targeting different regions of norovirus RdRp. In the future, structure-based drug design and rational optimization of known nucleoside and non-nucleoside inhibitors of norovirus RdRp may pave the way towards the next generation of direct-acting antivirals.
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33
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No! When the immunologist becomes a virologist: Norovirus – an emerging infection in immune deficiency diseases. Curr Opin Allergy Clin Immunol 2016; 16:557-564. [DOI: 10.1097/aci.0000000000000323] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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34
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Baldridge MT, Turula H, Wobus CE. Norovirus Regulation by Host and Microbe. Trends Mol Med 2016; 22:1047-1059. [PMID: 27887808 DOI: 10.1016/j.molmed.2016.10.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 10/05/2016] [Accepted: 10/05/2016] [Indexed: 12/16/2022]
Abstract
Norovirus (NoV) infection is the leading cause of epidemic gastroenteritis globally, and can lead to detrimental chronic infection in immunocompromised hosts. Despite its prevalence as a cause of diarrheal illness, the study of human NoVs (HNoVs) has historically been limited by a paucity of models. The use of murine NoV (MNoV) to interrogate mechanisms of host control of viral infection has facilitated the exploration of different genetic mouse models, revealing roles for both innate and adaptive immunity in viral regulation. MNoV studies have also recently identified important interactions between the commensal microbiota and NoV with clear extensions to HNoVs. In this review, we discuss the most current understanding of how the host, the microbiome, and their interactions regulate NoV infections.
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Affiliation(s)
- Megan T Baldridge
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO, USA.
| | - Holly Turula
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Christiane E Wobus
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
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35
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Bok K, Prevots DR, Binder AM, Parra GI, Strollo S, Fahle GA, Behrle-Yardley A, Johnson JA, Levenson EA, Sosnovtsev SV, Holland SM, Palmore TN, Green KY. Epidemiology of Norovirus Infection Among Immunocompromised Patients at a Tertiary Care Research Hospital, 2010-2013. Open Forum Infect Dis 2016; 3:ofw169. [PMID: 27800529 PMCID: PMC5084716 DOI: 10.1093/ofid/ofw169] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 08/05/2016] [Indexed: 11/13/2022] Open
Abstract
Background. Noroviruses are a major cause of infectious gastroenteritis worldwide, and viruses can establish persistent infection in immunocompromised individuals. Risk factors and transmission in this population are not fully understood. Methods. From 2010 through 2013, we conducted a retrospective review among immunocompromised patients (n = 268) enrolled in research studies at the National Institutes of Health Clinical Center and identified a subset of norovirus-positive patients (n = 18) who provided stool specimens for norovirus genotyping analysis. Results. Norovirus genome was identified by reverse-transcription quantitative polymerase chain reaction in stools of 35 (13%) of the 268 immunocompromised patients tested, and infection prevalence was 21% (11 of 53) in persons with primary immune deficiencies and 12% (20 of 166) among persons with solid tumors or hematologic malignancies. Among 18 patients with norovirus genotyping information, norovirus GII.4 was the most prevalent genotype (14 of 18, 78%). Persistent norovirus infection (≥6 months) was documented in 8 of 18 (44%) individuals. Phylogenetic analysis of the GII.4 capsid protein sequences identified at least 5 now-displaced GII.4 variant lineages, with no evidence of their nosocomial transmission in the Clinical Center. Conclusions. Norovirus was a leading enteric pathogen identified in this immunocompromised population. Both acute and chronic norovirus infections were observed, and these were likely community-acquired. Continued investigation will further define the role of noroviruses in these patients and inform efforts toward prevention and treatment.
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Affiliation(s)
- Karin Bok
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID)
| | | | | | - Gabriel I Parra
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID)
| | - Sara Strollo
- Laboratory of Clinical Infectious Disease, NIAID
| | - Gary A Fahle
- Microbiology Service, Clinical Center , National Institutes of Health , Bethesda, Maryland
| | - Allison Behrle-Yardley
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID)
| | - Jordan A Johnson
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID)
| | - Eric A Levenson
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID)
| | - Stanislav V Sosnovtsev
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID)
| | | | - Tara N Palmore
- Laboratory of Clinical Infectious Disease, NIAID; Hospital Epidemiology Service, National Institutes of Health Clinical Center
| | - Kim Y Green
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases (NIAID)
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Antiviral targets of human noroviruses. Curr Opin Virol 2016; 18:117-25. [PMID: 27318434 DOI: 10.1016/j.coviro.2016.06.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 06/06/2016] [Accepted: 06/06/2016] [Indexed: 11/20/2022]
Abstract
Human noroviruses are major causative agents of sporadic and epidemic gastroenteritis both in children and adults. Currently there are no licensed therapeutic intervention measures either in terms of vaccines or drugs available for these highly contagious human pathogens. Genetic and antigenic diversity of these viruses, rapid emergence of new strains, and their ability to infect a broad population by using polymorphic histo-blood group antigens for cell attachment, pose significant challenges for the development of effective antiviral agents. Despite these impediments, there is progress in the design and development of therapeutic agents. These include capsid-based candidate vaccines, and potential antivirals either in the form of glycomimetics or designer antibodies that block HBGA binding, as well as those that target essential non-structural proteins such as the viral protease and RNA-dependent RNA polymerase. In addition to these classical approaches, recent studies suggest the possibility of interferons and targeting host cell factors as viable approaches to counter norovirus infection. This review provides a brief overview of this progress.
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Thorne L, Arias A, Goodfellow I. Advances Toward a Norovirus Antiviral: From Classical Inhibitors to Lethal Mutagenesis. J Infect Dis 2016; 213 Suppl 1:S27-31. [PMID: 26744429 PMCID: PMC4704654 DOI: 10.1093/infdis/jiv280] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Human noroviruses are a leading cause of gastroenteritis worldwide, yet there are no licensed antivirals. There is an urgent need for norovirus therapeutics, particularly for chronic infections in immunocompromised individuals, but also a potential need for prophylactic use in epidemics. Continued research has led to the identification of compounds that inhibit norovirus replication in vitro and, at least in some cases, are also effective in vivo against murine norovirus. Progress has included classical approaches targeting viral proteins and harnessing the antiviral action of interferon, strategies targeting essential host cell factors, and novel strategies exploiting the high mutation rate of noroviruses.
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Affiliation(s)
- Lucy Thorne
- Division of Virology, Department of Pathology, University of Cambridge, Addenbrookes Hospital, United Kingdom
| | - Armando Arias
- Division of Virology, Department of Pathology, University of Cambridge, Addenbrookes Hospital, United Kingdom
| | - Ian Goodfellow
- Division of Virology, Department of Pathology, University of Cambridge, Addenbrookes Hospital, United Kingdom
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Abstract
INTRODUCTION Rapid transmission of norovirus often occurs due to its low infectious dosage, high genetic diversity and its short incubation time. The viruses cause acute gastroenteritis and may lead to death. Presently, no effective vaccine or selective drugs accepted by the United States Food and Drug Administration (FDA) are available for the treatment of norovirus. Advances in the development of norovirus replicon cell lines, GII.4-Sydney HuNoV strain human B cells, and murine and gnotobiotic pig norovirus models have facilitated the discovery of effective small molecule inhibitors in vitro and in vivo. AREAS COVERED This review gives a brief discussion of the biology and replication of norovirus before highlighting the discovery of anti-norovirus molecules. The article coverage includes: an overview of the current state of norovirus drug discovery, the targeting of the norovirus life cycle, the inhibition of structural and nonstructural proteins of norovirus such as proteases and polymerase, and the blockage of virus entry into host cells. Finally, anti-norovirus drugs in the clinical development stage are described. EXPERT OPINION The current approach for the counteraction of norovirus focuses on the inhibition of viral RNA polymerase, norovirus 3C-like protease and the structural proteins VP1 as well as the blockade of norovirus entry. Broad-spectrum anti-norovirus molecules, based on the inhibition of 3C-like protease, have been developed. Other host factors and ways to overcome the development of resistance through mutation are also being examined. A dual approach in targeting viral and host factors may lead to an effective counteraction of norovirus infection. Current successes in developing norovirus replicon harboring cells and norovirus infected human cells, as well as murine norovirus models and other animal models such as piglets have facilitated the discovery of effective drugs and helped our understanding of its mechanism of action.
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Affiliation(s)
- Sahani Weerasekara
- a Department of Chemistry , Kansas State University , Manhattan , KS , USA
| | - Allan M Prior
- b Molecular Sciences Institute, School of Chemistry , University of the Witwatersrand , Johannesburg , South Africa
| | - Duy H Hua
- a Department of Chemistry , Kansas State University , Manhattan , KS , USA
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Lei S, Ryu J, Wen K, Twitchell E, Bui T, Ramesh A, Weiss M, Li G, Samuel H, Clark-Deener S, Jiang X, Lee K, Yuan L. Increased and prolonged human norovirus infection in RAG2/IL2RG deficient gnotobiotic pigs with severe combined immunodeficiency. Sci Rep 2016; 6:25222. [PMID: 27118081 PMCID: PMC4846862 DOI: 10.1038/srep25222] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 04/13/2016] [Indexed: 02/04/2023] Open
Abstract
Application of genetically engineered (GE) large animals carrying multi-allelic modifications has been hampered by low efficiency in production and extended gestation period compared to rodents. Here, we rapidly generated RAG2/IL2RG double knockout pigs using direct injection of CRISPR/Cas9 system into developing embryos. RAG2/IL2RG deficient pigs were immunodeficient, characterized by depletion of lymphocytes and either absence of or structurally abnormal immune organs. Pigs were maintained in gnotobiotic facility and evaluated for human norovirus (HuNoV) infection. HuNoV shedding lasted for 16 days in wild type pigs, compared to 27 days (until the end of trials) in RAG2/IL2RG deficient pigs. Additionally, higher HuNoV titers were detected in intestinal tissues and contents and in blood, indicating increased and prolonged HuNoV infection in RAG2/IL2RG deficient pigs and the importance of lymphocytes in HuNoV clearance. These results suggest that GE immunodeficient gnotobiotic pigs serve as a novel model for biomedical research and will facilitate HuNoV studies.
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Affiliation(s)
- Shaohua Lei
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
| | - Junghyun Ryu
- Department of Animal and Poultry Sciences, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Ke Wen
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
| | - Erica Twitchell
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
| | - Tammy Bui
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
| | - Ashwin Ramesh
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
| | - Mariah Weiss
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
| | - Guohua Li
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
| | - Helen Samuel
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
| | - Sherrie Clark-Deener
- Department of Large Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
| | - Xi Jiang
- Division of Infectious Diseases, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Kiho Lee
- Department of Animal and Poultry Sciences, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Lijuan Yuan
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
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Abstract
Norovirus (NoV) is recognised as a leading cause of gastroenteritis worldwide across all age groups. The prevalence and diversity of NoVs in many African countries is still unknown, although early sero-prevalence studies indicated widespread early infection. Reports on NoVs in Africa vary widely in terms of study duration, population groups and size, inclusion of asymptomatic controls, as well as genotyping information. This review provides an estimate of NoV prevalence and distribution of genotypes of NoVs in Africa. Inclusion criteria for the review were study duration of at least 6 months, population size of >50 and diagnosis by RT-PCR. As regions used for genotyping varied, or genotyping was not always performed, this was not considered as an inclusion criteria. A literature search containing the terms norovirus+Africa yielded 74 publications. Of these 19 studies from 14 out of the 54 countries in Africa met the inclusion criteria. Data from studies not meeting the inclusion criteria, based on sample size or short duration, were included as discussion points. The majority of studies published focused on children, under five years of age, hospitalised with acute gastroenteritis. The mean overall prevalence was 13.5% (range 0.8–25.5%) in children with gastroenteritis and 9.7% (range 7–31%) in asymptomatic controls, where tested. NoV GII.4 was the predominant genotype identified in most of the studies that presented genotyping data. Other prevalent genotypes detected included GII.3 and GII.6. In conclusion, NoV is a common pathogen in children with diarrhoea in Africa, with considerable carriage in asymptomatic children. There is however, a paucity of data on NoV infection in adults.
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Affiliation(s)
- Janet Mans
- Department of Medical Virology, University of Pretoria, Pretoria, South Africa
- * E-mail:
| | - George E. Armah
- Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | - A. Duncan Steele
- MRC Diarrhoeal Pathogens Research Unit, University of Limpopo, Pretoria, South Africa
| | - Maureen B. Taylor
- Department of Medical Virology, University of Pretoria, Pretoria, South Africa
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Weerawarna PM, Kim Y, Galasiti Kankanamalage AC, Damalanka VC, Lushington GH, Alliston KR, Mehzabeen N, Battaile KP, Lovell S, Chang KO, Groutas WC. Structure-based design and synthesis of triazole-based macrocyclic inhibitors of norovirus protease: Structural, biochemical, spectroscopic, and antiviral studies. Eur J Med Chem 2016; 119:300-18. [PMID: 27235842 PMCID: PMC4916972 DOI: 10.1016/j.ejmech.2016.04.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/04/2016] [Accepted: 04/06/2016] [Indexed: 01/14/2023]
Abstract
Outbreaks of acute gastroenteritis caused by noroviruses constitute a public health concern worldwide. To date, there are no approved drugs or vaccines for the management and prophylaxis of norovirus infections. A potentially effective strategy for the development of norovirus therapeutics entails the discovery of inhibitors of norovirus 3CL protease, an enzyme essential for noroviral replication. We describe herein the structure-based design of the first class of permeable, triazole-based macrocyclic inhibitors of norovirus 3C-like protease, as well as pertinent X-ray crystallographic, biochemical, spectroscopic, and antiviral studies. Novel triazole-based macrocyclic inhibitors of norovirus 3CL protease were synthesized. The interplay of conformation and activity was probed using NMR and X-ray crystallography. Bound inhibitors assume a β-strand conformation according to X-ray crystal structure. Loss of critical hydrogen bonding interactions was revealed by X-ray crystallography.
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Affiliation(s)
| | - Yunjeong Kim
- Department of Diagnostic Medicine & Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | | | - Vishnu C Damalanka
- Department of Chemistry, Wichita State University, Wichita, KS 67260, USA
| | | | - Kevin R Alliston
- Department of Chemistry, Wichita State University, Wichita, KS 67260, USA
| | - Nurjahan Mehzabeen
- Protein Structure Laboratory, The University of Kansas, Lawrence, KS 66047, USA
| | - Kevin P Battaile
- IMCA-CAT, Hauptman-Woodward Medical Research Institute, APS Argonne National Laboratory, Argonne, IL 60439, USA
| | - Scott Lovell
- Protein Structure Laboratory, The University of Kansas, Lawrence, KS 66047, USA
| | - Kyeong-Ok Chang
- Department of Diagnostic Medicine & Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA.
| | - William C Groutas
- Department of Chemistry, Wichita State University, Wichita, KS 67260, USA.
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Green KY. Editorial Commentary: Noroviruses and B Cells. Clin Infect Dis 2016; 62:1139-40. [PMID: 26908783 DOI: 10.1093/cid/ciw063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 01/31/2016] [Indexed: 01/31/2023] Open
Affiliation(s)
- Kim Y Green
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
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Head MG, Lopman BA. Norovirus in 2016-Emesis Aplenty but Clear Signs of Progress. J Infect Dis 2016; 213 Suppl 1:S1-2. [PMID: 26744425 DOI: 10.1093/infdis/jiv409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The key theme emerging from the articles in this supplement is that burden of norovirus in the United Kingdom and elsewhere is substantial and that new tools for prevention, diagnosis, and treatment are required. Basic understanding of norovirus biology continues to accelerate, but parallel increases in capacity and research funding are going to be needed to translate this knowledge into clinical trials and translational research that can result in public health gains.
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Affiliation(s)
- Michael G Head
- Farr Institute for Health Informatics, University College London Faculty of Medicine, University of Southampton, United Kingdom
| | - Benjamin A Lopman
- Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
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Galasiti Kankanamalage AC, Weerawarna PM, Kim Y, Chang KO, Groutas WC. Anti-norovirus therapeutics: a patent review (2010-2015). Expert Opin Ther Pat 2016; 26:297-308. [PMID: 26881878 PMCID: PMC4948123 DOI: 10.1517/13543776.2016.1153065] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Human noroviruses are the primary causative agents of acute gastroenteritis and are a pressing public health burden worldwide. There are currently no vaccines or small molecule therapeutics available for the treatment or prophylaxis of norovirus infections. An improved understanding of norovirus biology, as well as the pathogenic mechanisms underlying the disease, has provided the impetus for a range of intense exploratory drug discovery efforts targeting viral and host factors. AREAS COVERED An overview of norovirus inhibitors disclosed in the patent literature (2010-present) and Clinicaltrials.gov is presented. The review is further enriched and supplemented by recent literature reports. EXPERT OPINION Seminal discoveries made in recent years, including a better understanding of the pathobiology and life cycle of norovirus, the identification and targeting of multiple viral and host factors, the advent of a replicon system and a small animal model for the preclinical evaluation of lead compounds, and the availability of high resolution X-ray crystal structures that can be utilized in structure-based drug design and lead optimization campaigns, collectively suggest that a small molecule therapeutic and prophylactic for norovirus infection is likely to emerge in the not too distant future.
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Affiliation(s)
| | | | - Yunjeong Kim
- Department of Diagnostic Medicine & Pathobiology, Manhattan, Kansas 66506, USA
| | - Kyeong-Ok Chang
- Department of Diagnostic Medicine & Pathobiology, Manhattan, Kansas 66506, USA
| | - William C. Groutas
- Department of Chemistry, Wichita State University, Wichita, Kansas 67260, USA
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Comparison of the BD MAX® Enteric Bacterial Panel assay with conventional diagnostic procedures in diarrheal stool samples. Eur J Clin Microbiol Infect Dis 2015; 35:131-6. [PMID: 26563899 DOI: 10.1007/s10096-015-2517-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 10/30/2015] [Indexed: 12/21/2022]
Abstract
Although infectious diarrhea is one of the most predominant diseases around the world, the identification of the causative microorganism is still challenging. The aim of this study was the evaluation of the BD MAX® Enteric Bacterial Panel assay in comparison to conventional diagnostic procedures concerning the detection of the enteric pathogens Salmonella spp., Campylobacter spp., Shigella spp., and Shiga toxin-producing Escherichia coli. For this purpose, 971 prospectively collected stool samples were evaluated. Utilization of the BD MAX Enteric Bacterial Panel elevated the overall detection rate from 5.26 % to 8.06 %. The positive percent agreement of the BD MAX Enteric Bacterial Panel assay and stool culture or enzyme immunoassay was 0.97 for Campylobacter spp., 0.75 for Salmonella spp., 1.00 for Shigella spp., and 0.88 for Shiga toxins. Furthermore, a negative percent agreement of 0.98 for Campylobacter spp., 0.99 for Salmonella spp., 0.99 for Shigella spp., and 0.99 for Shiga toxins has been demonstrated. This study highlighted the superior detection rate of molecular assays compared to conventional diagnostic procedures.
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Biochemical Evaluation of the Inhibition Properties of Favipiravir and 2'-C-Methyl-Cytidine Triphosphates against Human and Mouse Norovirus RNA Polymerases. Antimicrob Agents Chemother 2015; 59:7504-16. [PMID: 26392512 DOI: 10.1128/aac.01391-15] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 09/14/2015] [Indexed: 11/20/2022] Open
Abstract
Norovirus (NoV) is a positive-sense single-stranded RNA virus that causes acute gastroenteritis and is responsible for 200,000 deaths per year worldwide. No effective vaccine or treatment is available. Recent studies have shown that the nucleoside analogs favipiravir (T-705) and 2'-C-methyl-cytidine (2CM-C) inhibit NoV replication in vitro and in animal models, but their precise mechanism of action is unknown. We evaluated the molecular interactions between nucleoside triphosphates and NoV RNA-dependent RNA polymerase (NoVpol), the enzyme responsible for replication and transcription of NoV genomic RNA. We found that T-705 ribonucleoside triphosphate (RTP) and 2CM-C triphosphate (2CM-CTP) equally inhibited human and mouse NoVpol activities at concentrations resulting in 50% of maximum inhibition (IC50s) in the low micromolar range. 2CM-CTP inhibited the viral polymerases by competing directly with natural CTP during primer elongation, whereas T-705 RTP competed mostly with ATP and GTP at the initiation and elongation steps. Incorporation of 2CM-CTP into viral RNA blocked subsequent RNA synthesis, whereas T-705 RTP did not cause immediate chain termination of NoVpol. 2CM-CTP and T-705 RTP displayed low levels of enzyme selectivity, as they were both recognized as substrates by human mitochondrial RNA polymerase. The level of discrimination by the human enzyme was increased with a novel analog of T-705 RTP containing a 2'-C-methyl substitution. Collectively, our data suggest that 2CM-C inhibits replication of NoV by acting as a classic chain terminator, while T-705 may inhibit the virus by multiple mechanisms of action. Understanding the precise mechanism of action of anti-NoV compounds could provide a rational basis for optimizing their inhibition potencies and selectivities.
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Kim Y, Galasiti Kankanamalage AC, Chang KO, Groutas WC. Recent Advances in the Discovery of Norovirus Therapeutics. J Med Chem 2015; 58:9438-50. [PMID: 26258852 DOI: 10.1021/acs.jmedchem.5b00762] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Noroviruses are members of the family Caliciviridae. Norovirus infections are a global health burden that impacts >20 million individuals annually in the U.S. alone. Noroviruses are associated with high morbidity among vulnerable populations, particularly immunocompromised patients. This perspective highlights recent developments related to the discovery and development of norovirus-specific small-molecule therapeutics as well as recent advances in our understanding of norovirus biology and pathogenesis. Most of the work in this area is at the early discovery stage and has been primarily focused on inhibitors of norovirus 3C-like protease and RNA dependent RNA polymerase. However, recent discoveries emanating from basic studies in norovirus research have resulted in the identification of new host-related drug targets that can be exploited. A repurposed compound has been advanced to human clinical studies.
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Affiliation(s)
- Yunjeong Kim
- Department of Diagnostic Medicine & Pathobiology, College of Veterinary Medicine, Kansas State University , Manhattan, Kansas 66506, United States
| | | | - Kyeong-Ok Chang
- Department of Diagnostic Medicine & Pathobiology, College of Veterinary Medicine, Kansas State University , Manhattan, Kansas 66506, United States
| | - William C Groutas
- Department of Chemistry, Wichita State University , 1845 North Fairmount Avenue, Wichita, Kansas 67260, United States
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Garaicoechea L, Aguilar A, Parra GI, Bok M, Sosnovtsev SV, Canziani G, Green KY, Bok K, Parreño V. Llama nanoantibodies with therapeutic potential against human norovirus diarrhea. PLoS One 2015; 10:e0133665. [PMID: 26267898 PMCID: PMC4534396 DOI: 10.1371/journal.pone.0133665] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 06/30/2015] [Indexed: 11/24/2022] Open
Abstract
Noroviruses are a major cause of acute gastroenteritis, but no vaccines or therapeutic drugs are available. Llama-derived single chain antibody fragments (also called VHH) are small, recombinant monoclonal antibodies of 15 kDa with several advantages over conventional antibodies. The aim of this study was to generate recombinant monoclonal VHH specific for the two major norovirus (NoV) genogroups (GI and GII) in order to investigate their potential as immunotherapy for the treatment of NoV diarrhea. To accomplish this objective, two llamas were immunized with either GI.1 (Norwalk-1968) or GII.4 (MD2004) VLPs. After immunization, peripheral blood lymphocytes were collected and used to generate two VHH libraries. Using phage display technology, 10 VHH clones specific for GI.1, and 8 specific for GII.4 were selected for further characterization. All VHH recognized conformational epitopes in the P domain of the immunizing VP1 capsid protein, with the exception of one GII.4 VHH that recognized a linear P domain epitope. The GI.1 VHHs were highly specific for the immunizing GI.1 genotype, with only one VHH cross-reacting with GI.3 genotype. The GII.4 VHHs reacted with the immunizing GII.4 strain and showed a varying reactivity profile among different GII genotypes. One VHH specific for GI.1 and three specific for GII.4 could block the binding of homologous VLPs to synthetic HBGA carbohydrates, saliva, and pig gastric mucin, and in addition, could inhibit the hemagglutination of red blood cells by homologous VLPs. The ability of Nov-specific VHHs to perform well in these surrogate neutralization assays supports their further development as immunotherapy for NoV treatment and immunoprophylaxis.
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Affiliation(s)
| | - Andrea Aguilar
- Instituto de Virología, INTA, Castelar, Buenos Aires, Argentina
| | - Gabriel I. Parra
- Laboratory of Infectious Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Marina Bok
- Instituto de Virología, INTA, Castelar, Buenos Aires, Argentina
| | - Stanislav V. Sosnovtsev
- Laboratory of Infectious Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, United States of America
| | | | - Kim Y. Green
- Laboratory of Infectious Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Karin Bok
- Laboratory of Infectious Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Viviana Parreño
- Instituto de Virología, INTA, Castelar, Buenos Aires, Argentina
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Abstract
PURPOSE OF REVIEW Diarrhea is a common complaint in the solid organ transplant recipient. Unlike the immune-competent patient, diarrhea in an organ transplant recipient may result in dehydration, increased toxicity of medications, and rejection. There is a wide range of causes for diarrhea in transplant recipients, but the most common causes are Clostridium difficile infection, cytomegalovirus, and norovirus. This review will focus on new epidemiology data as to the cause of diarrhea in the transplant population. RECENT FINDINGS Recent data have identified C. difficile, cytomegalovirus, and norovirus as important causes of diarrhea in this population, and management should be focused on these causes. Newer diagnostic platforms (such as PCR) are being evaluated, which may help in identification of the cause of diarrhea. SUMMARY New epidemiologic data and new testing techniques offer an opportunity for research into better testing strategies for transplant patients with diarrhea. These newer testing strategies may offer better insight into the cause of diarrhea and more appropriate treatment for this illness.
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Affiliation(s)
- Michael Angarone
- aDivision of Infectious Diseases bDivision of Organ Transplantation, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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50
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Bozkurt H, D'Souza DH, Davidson PM. Thermal Inactivation of Foodborne Enteric Viruses and Their Viral Surrogates in Foods. J Food Prot 2015; 78:1597-617. [PMID: 26219377 DOI: 10.4315/0362-028x.jfp-14-487] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Foodborne viruses, in particular human norovirus and hepatitis A virus, are the most common causes of food-associated infections and foodborne illness outbreaks around the world. Since it is currently not possible to cultivate human noroviruses and the wild-type strain of hepatitis A virus in vitro, the use of a variety of viral surrogates is essential to determine appropriate thermal processing conditions to reduce the risk associated with their contamination of food. Therefore, the objectives of this review are to (i) present pertinent characteristics of enteric foodborne viruses and their viral surrogates, (ii) discuss the viral surrogates currently used in thermal inactivation studies and their significance and value, (iii) summarize available data on thermal inactivation kinetics of enteric viruses, (iv) discuss factors affecting the efficacy of thermal treatment, (v) discuss suggested mechanisms of thermal inactivation, and (vi) provide insights on foodborne enteric viruses and viral surrogates for future studies and industrial applications. The overall goal of this review is to contribute to the development of appropriate thermal processing protocols to ensure safe food for human consumption.
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Affiliation(s)
- Hayriye Bozkurt
- Department of Food Science and Technology, University of Tennessee, 2605 River Drive, Knoxville, Tennessee 37996-4591, USA
| | - Doris H D'Souza
- Department of Food Science and Technology, University of Tennessee, 2605 River Drive, Knoxville, Tennessee 37996-4591, USA
| | - P Michael Davidson
- Department of Food Science and Technology, University of Tennessee, 2605 River Drive, Knoxville, Tennessee 37996-4591, USA.
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